4.3GL PEFS Volvo I/O Starts and then dies

[jimi]

Four Winns 2000, 180 Horizon
Volvo Penta Sterndrive, Engine 4.3GL PEFS & Outdrive (SX-M 1.79)

Started and ran on the muffs for a couple of minutes outside the garage. Had almost no gas in the tank (son used it last and stored it last fall J ) but ran ok.

Launched the boat at the marina, filled up the tank and drove away from the dock. It was a little rough trying to come up on plane, stop and checked the ignition leads. Seemed like #3 might have been loose because it sound like it clicked when pressed on. Might have been bumped off while re-installing the block water drain plugs.

Restarted, engine ran great and drove over a mile to my dock with no issues. Later that afternoon went for a drive and the motor cut out while on plane at 20+ mph after ½ a mile. I attributed the engine stopping to possible water in the bottom of the fuel tank (remember I started it with almost nothing in the tank outside the garage) Restarted fine and drove another ¼ mile and it cut out again while on plane at 20+ mph. Restarted fine and drove ¾ mile back to my dock no issues.

The next day, (while the wife was watching) it cut out right after starting every time. Once (only once) the tachometer swung up to 2500 and back down to 0 after the engine cut as if possessed by some boat demon. I must have tied 10 times over 20 minutes but every time it cut right after firing.

Based on what I’ve read I’m planning on…

1. Turn the key to the run position and see if I have 12Vdc on the purple wire of your coil
2. Then I’ll check to make sure it’s not being cut off right after I release the key.
3. I'll check for 12Vdc at the fuel pump both during cranking and right afterwards.

The boat is located up north (~3hrs drive where there is no internet) so I want to collect a complete list of items to check next weekend. Any other likely items to check?

 

[Scott Danforth]

check your fuel pump relay power. you get power from the starter to the fuel pump when cranking and you get power thru the oil pressure switch when you are not cranking.

 

[alldodge]

I think you have a good plan. Sounds to me your loosing voltage at the coil. Might be the key switch or connection to it

 

[jimi]

So I bought a new alternator and went up north and retested the engine before installing the new alternator... same issue, starts and dies. Checked all the connections and found one on the back of the alternator that “might” have been bad because there was a little bit of calcium. Tired the key again and bingo ran fine. Started and ran every time! So I assumed that it was a bad connection and returned the alternator for a refund.

The next week the boat would “start and die” every try. Then I jumped the coil (removed the purple wire on the backside of the alternator and ran a jumper to the battery. Boat started and ran fine. Reinstalled the purple wire to the back of the alternator. Boat started and ran fine all weekend.
Jumped the coil from the battery and bingo ran. Turn off the motor and it restarted perfectly; no jumping. Boat started and ran fine all weekend.

The next weekend “starts and dies”. Jumped the coil once and then the boat started and ran fine all weekend. Re-ordered the alternator Monday.

I installed the new alternator just this last weekend and had the same “starts and dies”. Jumped between the battery and the purple post on the backside of the new alternator (did not remove purple wire from alternator) and got the motor running. Removed the jumper and the engine died. Ahhh… Jumped it twice more and then the engine stayed running. The remained of the weekend (1 day), the engine started every time and stayed running (until I turned it off). On the positive side, I am getting higher and more consistent voltage from the alternator. With the losses through the cabling between the battery and the dash, my dash mounted voltmeter used to read 12ish volts and now it is solidly 13+ volts when the engine is running. So I suspect my alternator output was dropping off.

Clearly, I have no idea what I’m doing… help

 

[criscolumbus]

based on the wiring diagram your fuel pump is powered through the fuel pump relay which is operated 2 ways. 1) the wire from the ignition switch which is a ground when starting. 2) the alternator L2 terminal which is a ground when the alternator is charging.

I don't think you have a problem with the fuel pump based on your previous posts.

again based on the diagram the Ignition coil is powered via the purple wire which is 12+ when the ignition is in the on position and I assume also when it is in start position but not sure. The purple wire is additionally connected to the temp/oil pressure alarm, Alternator Excite terminal, the ignition coil, and also the starter (R) terminal. The R terminal at the starter is usually used to power the ignition when starting without going through a resistor when there is a points ignition but in this case you have no resistor because it is an electronic ignition so I am not sure why the purple wire is connected to the starter (R) terminal.

Based on your description, I would try to trouble shoot the purple wire (ignition power source) when it will not start and before you do the coil jump thing.

 

[criscolumbus]

here is your wiring diagram

http://162.144.28.33/lib/volvo/manuals/ef_wiring.html#/6

 

[alldodge]

It sounds to me that there is a bad splice inside the harness. Runs fine with jumpers and will also run sometimes fine without them. Then it will start dying again.

The voltmeter on the boat use to show 12 now its showing 13+ so this is an issue with the excite wire (purple) or the field wire (orange).

 

[jimi]

Great guys. I have a plan for next Saturday morning.

It is possible the ignition swith has become a "maybe" switch.

I'll to trouble shoot the purple wire (ignition power source) before jumping anything. Then, if that doesn't do it I'll look at the field wire (orange).

Thx,

 

[jimi]

So just spent lunch looking the 4.3 GL wirings diagram (thanks cris columbus I only had the shop manual not the wiring diagram supplement) and noticed the purple wiring running from the alternator to the horn.
So … initially after installing the new alternator and the motor dying right after start, I left the key in “run” and started poking around. When I touched the back of the horn, it started screaming at me (it should have come on as soon the motor cut out). I wonder if the horn is shorting out? Would that cause the issue I am having?
One more tide bit, during the week I store my boat on a railway (steep uphill grade). When I arrive and launch the boat (foot of the railway) I have this “start and die” issue. I then paddle to the dock and do whatever jumping. Once the motor is running fine for the weekend it stays by the dock (level), it never goes up the railway again until Sunday night.

 

[criscolumbus]

So just spent lunch looking the 4.3 GL wirings diagram (thanks cris columbus I only had the shop manual not the wiring diagram supplement) and noticed the purple wiring running from the alternator to the horn.
So … initially after installing the new alternator and the motor dying right after start, I left the key in “run” and started poking around. When I touched the back of the horn, it started screaming at me (it should have come on as soon the motor cut out). I wonder if the horn is shorting out? Would that cause the issue I am having?
One more tide bit, during the week I store my boat on a railway (steep uphill grade). When I arrive and launch the boat (foot of the railway) I have this “start and die” issue. I then paddle to the dock and do whatever jumping. Once the motor is running fine for the weekend it stays by the dock (level), it never goes up the railway again until Sunday night.

I doubt the horn is shorting out. If it did you would blow a fuse, trip a breaker, and or the wire would go up in smoke.

 

[alldodge]

(steep uphill grade)

Just another guess, the fuel tank pick up should be in a place closest to the stern. If the boat is stored facing down, ten there is a possibility it was sucking nothing but air. If it was stored bow up, then no

Is the battery firmly installed so it doesn't move?

 

[criscolumbus]

CORRCTION -- Post #5

This has nothing to do with the problem but wanted to clarify. In post #5 above I incorrectly stated the fuel pump relay is activated by ground.

The fuel pump relay is activated by power through a diode to the fuel pump relay both from 1) the Alternator. 2) the Start relay output.

 

[mikemj]

the purple wire is your lifeline in the system.when you start the engine the purple wire on starter powers the fuel pump. after started then the alt takes over to power the fuel pump. the coil has power thru purple wire all the time.,but change the coil and control module under dist cap out sounds like a ignition issue . they work together

 

[mikemj]

also disconnect the main wire harness( big round plug held with hose clamp) check for corrosion

 

[jimi]

AllDodge
The boat goes up hill on the railway, so the stern is always down. I doubt that air in the fuel line is an issue. The engine starts and cuts immediately after releasing the key.

The battery and its contacts are secure

mikemj
I’ll check the main engine harness connector for corrosion this weekend.
Do you think it is the coil or control module? After jumping the purple wire at the alternator, the engine is 100% reliable and starts every time!

All
I’m leaning toward a wire or relay issue. If the "purple" came from the engine harness connector to the horn and then to the alternator, then a corroded crimp lug on the back of the horn might prevent power from going to the horn and alternator...

​​​​​​​I think I'm going to spend some time tracing and checking wires this weekend. Any other ideas?

 

[criscolumbus]

Four Winns 2000, 180 Horizon
Volvo Penta Sterndrive, Engine 4.3GL PEFS & Outdrive (SX-M 1.79)



Based on what I’ve read I’m planning on…

1. Turn the key to the run position and see if I have 12Vdc on the purple wire of your coil
2. Then I’ll check to make sure it’s not being cut off right after I release the key.
3. I'll check for 12Vdc at the fuel pump both during cranking and right afterwards.

The boat is located up north (~3hrs drive where there is no internet) so I want to collect a complete list of items to check next weekend. Any other likely items to check?

Did you every try your planned checks? if so what was the outcome of each of the 3 tests?

With the key on but engine not running, do you have 12 volts at the coil?

 

[jimi]

Good point, I’m not 100% sure. Once I "jumped" the purple wire to the coil the fault went away so everything went normal for the remainder of the weekend.

"Hopefully" the boat has the same symptom Saturday when I first go to start it. Then I can do those checks.

 

[jimi]

While we’re on the topic

1. Turn the key to the run position and see if I have 12Vdc on the purple wire of your coil
   1. So if the engine is not running and I turn the key to the run position there will be no voltage on the coil (purple) because…
      1. in the Run position, the stater relay has dropped off and the starter solenoid is no longer sending +12Vdc to the coil, and
      2. without the engine turning, the alternator is not putting out +12 Vdc, so no power to coil either.
2. Then I’ll check to make sure it’s not being cut off right after I release the key.
   1. But if the engine dies as soon as it starts, then the alternator isn’t spinning and there couldn’t be any +12 Vdc right?
3. I'll check for 12Vdc at the fuel pump both during cranking and right afterwards.
   1. I’m pretty sure I heard the fuel pump whine but after the engine died I’m not sure. This I’ll check for sure

 

[criscolumbus]

While we’re on the topic

1. Turn the key to the run position and see if I have 12Vdc on the purple wire of your coil
   1. So if the engine is not running and I turn the key to the run position there will be no voltage on the coil (purple) because…
      1. in the Run position, the stater relay has dropped off and the starter solenoid is no longer sending +12Vdc to the coil, and
      2. without the engine turning, the alternator is not putting out +12 Vdc, so no power to coil either.
2. Then I’ll check to make sure it’s not being cut off right after I release the key.
   1. But if the engine dies as soon as it starts, then the alternator isn’t spinning and there couldn’t be any +12 Vdc right?
3. I'll check for 12Vdc at the fuel pump both during cranking and right afterwards.
   1. I’m pretty sure I heard the fuel pump whine but after the engine died I’m not sure. This I’ll check for sure

#1 - NO, I think power comes from the Batt. to the ignition key and while in the on position, it goes out the purple wire to the coil. so, with the key on and engine not running, there should be 12v at the + side of the coil. The purple wire connection at the alternator is used to "excite" the alternator to get it started charging. Again it is unclear to me if this "just happens to" provide power out when charging but I think even if it does, that was not the intent. So my guess is something is wrong between the coil and the ignition key. The starter R terminal is powering the ignition when cranking, and once you get it up and going the Alternator maybe is keeping it running. the part that is missing, if this were the case, how would you turn the engine off? so I still don't have my head wrapped around it but if you fill in the blanks by making only one change at a time, you should be able to isolate the problem.

 

[jimi]

Makes sense,... hopeful the problem is there r when I try to start it this weekend and I'll pick my way along the food chain (battery, ignition switch, coil...). Thx